Bring three (python) packages into AthAnalysis.
These are required to import the ConfigFlags.Trigger
With this (and the complimentary MR !43072 (merged)), the Component Accumulator based TrigDecisionToolConfig.py can be used in AthAnalysis.
cc @fwinkl: I had to exclude the --extend-extensions CMake here, it isn't recognised in AthAnalysis.
Adding expert review labels as adds packages to the build.